com.numericalmethod.suanshu.matrix.doubles
Interface MatrixAccessor

All Known Subinterfaces:

Matrix, SparseMatrix

All Known Implementing Classes:

BidiagonalMatrix, BorderedHessian, CovarianceMatrix, CsrSparseMatrix, DenseMatrix, DiagonalMatrix, DokSparseMatrix, GivensMatrix, GoldfeldQuandtTrotter, Gradient, Hessian, HilbertMatrix, ImmutableKroneckerProduct, ImmutableMatrix, Inverse, Jacobian, JordanExchange, KroneckerProduct, LilSparseMatrix, LowerTriangularMatrix, MatrixMathImpl, MatrixStorageImpl, MatthewsDavies, PermutationMatrix, Pow, PseudoInverse, SubMatrixRef, SymmetricMatrix, TriangularMatrix, TridiagonalMatrix, UpperTriangularMatrix

public interface MatrixAccessor

This interface defines methods for accessing elements in a matrix.

Indices count from 1, e.g., get(1,1), which is what mathematicians (not programmers) are accustomed to.

Invalid access such as using out-of-range indices or altering immutable matrix will lead to MatrixAccessException.

The only way to change a matrix is by set(int, int, double). Other operations that "change" the matrix actually creates a new and independent copy.

Method Summary

double	get(int row, int col) Get the matrix entry at [row, col].
Vector	getColumn(int col) Get a specified column as a vector.
Vector	getRow(int row) Get a specified row as a vector.
void	set(int row, int col, double value) Set the matrix entry at [row, col] to value.

Method Detail

set

void set(int row,
         int col,
         double value)
         throws MatrixAccessException

Set the matrix entry at [row, col] to value.

This is the only method that may change the entries of a matrix.

Parameters:

row - the row index

col - the column index

value - the value to set A[row, col] to

Throws:

MatrixAccessException - if row or col is out of range

get

double get(int row,
           int col)
           throws MatrixAccessException

Get the matrix entry at [row, col].

Parameters:

row - the row index

col - the column index

Returns:

A[row, col]

Throws:

MatrixAccessException - if row or col is out of range

getRow

Vector getRow(int row)
              throws MatrixAccessException

Get a specified row as a vector.

Parameters:

row - the row index

Returns:

a vector A[row, ]

Throws:

MatrixAccessException - when row < 1, or when row > number of rows

getColumn

Vector getColumn(int col)
                 throws MatrixAccessException

Get a specified column as a vector.

Parameters:

col - the column index

Returns:

a vector A[, col]

Throws:

MatrixAccessException - when col < 1, or when col > number of columns